Uncommon adrenal rest tumors and massive adrenal enlargement in adult with congenital adrenal hyperplasia mimicking metastasis from pleomorphic sarcoma.

BACKGROUND: Congenital adrenal hyperplasia (CAH) encompassed a bunch of autosomal recessive disorders characterized by impaired cortisol levels due to an enzymatic deficiency in steroid synthesis. In adult male patients with CAH, a frequent complication related to poor disease control is the development of ectopic adrenocortical tissue in the testes, named testicular adrenal rest tumors (TART). Conversely, ovarian adrenal rest tumors (OART) in females are extremely rare and adrenal rests in sites other than gonads are so uncommon to have been described only few times in literature. CASE PRESENTATION: We report a case of a male patient with untreated CAH and oncologic history of pleomorphic sarcoma who presented with massive bilateral adrenal enlargement and adrenal rest tumors in peri-lumbar and peri-cecal sites, which mimicked metastasis from sarcoma. CONCLUSIONS: The development of massive adrenal enlargement and ectopic adrenal rest tumors in sites other than gonads, even if very uncommon, should be suspected in patients with CAH and prolonged periods of undertreatment.

Congenital Adrenal Hyperplasia - A Comprehensive Review of Genetic Studies on 21-Hydroxylase Deficiency from India.

Congenital adrenal hyperplasia (CAH) comprises a heterogeneous group of autosomal recessive disorders impairing adrenal steroidogenesis. Most cases are caused by mutations in the CYP21A2 gene resulting in 21-hydroxylase (21-OH) deficiency (21-OHD). The genetics of 21-OH CAH is complexed by a highly homologous pseudogene CYP21A1P imposing several limitations in the molecular analysis. Therefore, genetic testing is still not a part of routine CAH diagnosis and is mainly dependent on 17-hydroxy progesterone (OHP) measurements. There are very few reports of CYP21A2 gene analysis from India and there is no comprehensive review available on genetic testing and the spectrum of CYP21A2 mutations from the country. This review focuses on the molecular aspects of 21-OHD and the genetic studies on CYP21A2 gene reported from India. The results of these studies insist the compelling need for large-scale CYP21A2 genetic testing and newborn screening (NBS) in India. With a high disease prevalence and consanguinity rates, robust and cost-effective genetic testing for 21-OH CAH would enable an accurate diagnosis in routine clinical practice. Whereas establishing affordable genotyping assays even in secondary care or resource-poor settings of the country can identify 90% of the mutations that are pseudogene derived, initiatives on reference laboratories for CAH across the nation with comprehensive genetic testing facilities will be beneficial in those requiring extended analysis of CYP21A2 gene. Further to this, incorporating genetic testing in NBS and carrier screening programmes will enable early diagnosis, better risk assessment and community-based management.

Current Advances in the Management of Congenital Adrenal Hyperplasia.

Congenital adrenal hyperplasia (CAH) is an autosomal recessive genetic condition caused by various enzyme deficiencies that result in disruptions of pathways of adrenal steroidogenesis. 21-hydroxylase deficiency is the most common form of CAH and has a variable phenotype which ranges a spectrum, from the most severe salt-wasting type to the simple-virilizing type and the least severe nonclassical form. Patients with CAH are at risk for various comorbidities due to the underlying adrenal hormone production imbalance as well as the treatment of the condition, which typically includes supraphysiologic glucocorticoid dosing. Children and adults require frequent monitoring and careful medication dosing adjustment. However, there are multiple novel therapies on the horizon that offer promise to patients with CAH in optimizing their treatment regimens and reducing the risk of comorbidities.

Memory in female adolescents with congenital adrenal hyperplasia due to 21-hydroxylase deficiency.

INTRODUCTION: In females with congenital adrenal hyperplasia (CAH), the influence of hyperandrogenism and glucocorticoid supplementation on neurocognition is controversial. OBJECTIVES: To identify possible differences in visual working memory and verbal memory in adolescent girls with CAH due to 21-hydroxylase deficiency and matched controls. Moreover, to study if any relationship between variables associated with CAH and the scores of the selected memory tests was present. MATERIAL AND METHODS: In total 39 individuals were studied, female adolescents with CAH and age and pubertal stage matched healthy male and female controls (13 in each group). Sociodemographic, clinical, hormonal, and neurocognitive variables were explored. In female adolescents with CAH, variables related to the disease (age at diagnosis, clinical form, time since diagnosis, and glucocorticoid doses) were correlated with the scores obtained for neurocognitive variables. RESULTS: The mean age was 13.9 ± 3.3 years. In female adolescents with CAH the results were worse compared to controls in Free Recall (p = 0.039) and in Visual Memory Span score (p = 0.016). Age at diagnosis was negatively correlated to number of hits (p = 0.04), number recalled backward (p = 0.03), Visual Memory Span test score (p = 0.04) and Total Free Recall (p = 0.04), i.e., memory was worse with later diagnosis. CONCLUSIONS: Female adolescents with CAH had worse visual working memory compared to matched controls, but not in verbal memory. Age at diagnosis was negatively associated with the memory tests.

Challenging Molecular Diagnosis of Congenital Adrenal Hyperplasia (CAH) Due to 21-Hydroxylase Deficiency: Case Series and Novel Variants of CYP21A2 Gene.

Congenital adrenal hyperplasia (CAH) is a group of autosomal recessive genetic defects in cortisol synthesis and shows elevated ACTH concentrations, which in turn has downstream effects. The most common variant of CAH, 21-hydroxylase deficiency (21OHD), is the result of pathogenic variants in the CYP21A2 gene and is one of the most common monogenic disorders. However, the genetics of 21OHD is complex and challenging. The CYP21A2 gene is located in the RCCX copy number variation (CNV), a complex, multiallelic, and tandem CNV in the major histocompatibility complex (MHC) class III region on chromosome 6 (band 6p21.3). Here, CYP21A2 and its pseudogene CYP21A1P are located 30 kb apart and share a high nucleotide homology of approximately 98% and 96% in exons and introns, respectively. This high-sequence homology facilitates large structural rearrangements, copy number changes, and gene conversion through intergenic recombination. There is a good genotype-phenotype correlation in 21OHD, and genotyping can be performed to confirm the clinical diagnosis, predict long-term outcomes, and determine genetic counseling. Thus, genotyping in CAH is clinically relevant but the interpretations can be challenging for non-initiated clinicians. Here, there are some concrete examples of how molecular diagnosis can sometimes require the use of multiple molecular strategies.

Abiraterone in Classic Congenital Adrenal Hyperplasia: Results of Medical Therapy Before Adrenalectomy.

We present the case of a 20-year-old woman with classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency, with uncontrolled hyperandrogenemia despite supraphysiological glucocorticoid therapy. We used abiraterone acetate, an inhibitor of the 17-hydroxylase/17,20-lyase enzyme, to suppress adrenal androgen synthesis and allow physiological glucocorticoid and mineralocorticoid therapy, as a proof-of-concept, before proceeding to bilateral adrenalectomy. We report the patient's clinical course, the changes in adrenal steroids, and the immunohistochemistry of the adrenals.

Genetic Disruption of cyp21a2 Leads to Systemic Glucocorticoid Deficiency and Tissues Hyperplasia in the Teleost Fish Medaka (Oryzias latipes).

cytochrome P-450, 21-hydroxylase (cyp21a2), encodes an enzyme required for cortisol biosynthesis, and its mutations are the major genetic cause of congenital adrenal hyperplasia (CAH) in humans. Here, we have generated a null allele for the medaka cyp21a2 with a nine base-pair insertion which led to a truncated protein. We have observed a delay in hatching and a low survival rate in homozygous mutants. The interrenal gland (adrenal counterpart in teleosts) exhibits hyperplasia and the number of pomca-expressing cells in the pituitary increases in the homozygous mutant. A mass spectrometry-based analysis of whole larvae confirmed a lack of cortisol biosynthesis, while its corresponding precursors were significantly increased, indicating a systemic glucocorticoid deficiency in our mutant model. Furthermore, these phenotypes at the larval stage are rescued by cortisol. In addition, females showed complete sterility with accumulated follicles in the ovary while male homozygous mutants were fully fertile in the adult mutants. These results demonstrate that the mutant medaka recapitulates several aspects of cyp21a2-deficiency observed in humans, making it a valuable model for studying steroidogenesis in CAH.

Isotretinoin-unresponsive acne as a sign of a congenital disorder: a case of 21-hydroxylase deficiency.

Acne is a multifactorial and common disorder among young people and a frequent reason for dermatology consultation. When moderate-to-severe acne is not responsive to conventional treatments, oral isotretinoin is a very effective solution. However, there are cases in which this treatment fails to produce the expected results. In this case, an 18-year-old male patient with acne, unresponsive to traditional acne therapies, experienced only a partial benefit from oral isotretinoin. Endocrinology consultation and hormonal work-up revealed androgen metabolism anomalies suggestive of a non-classical form of congenital adrenal hyperplasia due to 21-hydroxylase deficiency. In this case report, the authors discuss when to suspect, how to diagnose, and how to manage similar cases.

Landscape of congenital adrenal hyperplasia cases in adult endocrinology clinics of Türkiye-a nation-wide multicentre study.

BACKGROUND AND AIMS: Congenital adrenal hyperplasia (CAH) is a group of disorders that affect the production of steroids in the adrenal gland and are inherited in an autosomal recessive pattern. The clinical and biochemical manifestations of the disorder are diverse, ranging from varying degrees of anomalies of the external genitalia to life-threatening adrenal insufficiency. This multicenter study aimed to determine the demographics, biochemical, clinical, and genetic characteristics besides the current status of adult patients with CAH nationwide. METHODS: The medical records of 223 patients with all forms of CAH were evaluated in the study, which included 19 adult endocrinology clinics. A form inquiring about demographical, etiological, and genetic (where available) data of all forms of CAH patients was filled out and returned by the centers. RESULTS: Among 223 cases 181 (81.16%) patients had 21-hydroxylase deficiency (21OHD), 27 (12.10%) had 11-beta-hydroxylase deficiency (110HD), 13 (5.82%) had 17-hydroxylase deficiency (17OHD) and 2 (0.89%) had 3-beta-hydroxysteroid-dehydrogenase deficiency. 21OHD was the most prevalent CAH form in our national series. There were 102 (56.4%) classical and 79 (43.6%) non-classical 210HD cases in our cohort. The age of the patients was 24.9 ± 6.1 (minimum-maximum: 17-44) for classical CAH patients and 30.2 ± 11.2 (minimum-maximum: 17-67). More patients in the nonclassical CAH group were married and had children. Reconstructive genital surgery was performed in 54 (78.3%) of classical CAH females and 42 (77.8%) of them had no children. Thirty-two (50.8%) NCAH cases had homogenous and 31 (49.2%) had heterogeneous CYP21A2 gene mutations. V281L pathological variation was the most prevalent mutation, it was detected in 35 (55.6%) of 21OHD NCAH patients. CONCLUSION: Our findings are compatible with the current literature except for the higher frequency of 110HD and 17OHD, which may be attributed to unidentified genetic causes. A new classification for CAH cases rather than classical and non-classical may be helpful as the disease exhibits a large clinical and biochemical continuum. Affected cases should be informed of the possible complications they may face. The study concludes that a better understanding of the clinical characteristics of patients with CAH can improve the management of the disorder in daily practice.

Frequency of stress dosing and adrenal crisis in paediatric and adult patients with congenital adrenal hyperplasia: a prospective study.

OBJECTIVE: Patients with congenital adrenal hyperplasia (CAH) require life-long glucocorticoid replacement, including stress dosing (SD). This study prospectively assessed adrenal crisis (AC) incidence, frequency, and details of SD and disease knowledge in adult and paediatric patients and their parents. DESIGN: Prospective, observational study. METHODS: Data on AC and SD were collected via a patient diary. In case of AC, medical records were reviewed and patient interviews conducted. Adherence to sick day rules of the German Society of Endocrinology (DGE) and disease knowledge using the German version of the CAH knowledge assessment questionnaire (CAHKAQ) were assessed. RESULTS: In 187 adult patients, the AC incidence was 8.4 per 100 patient years (py) and 5.1 in 100 py in 38 children. In adults, 195.4 SD episodes per 100 py were recorded, in children 169.7 per 100 py. In children 72.3% and in adults 34.8%, SD was performed according to the recommendations. Children scored higher on the CAHKAQ than adults (18.0 [1.0] vs 16.0 [4.0]; P = .001). In adults, there was a positive correlation of the frequency of SD and the incidence of AC (r = .235, P = .011) and CAHKAQ score (r = .233, P = .014), and between the incidence of AC and CAHKAQ (r = .193, P = .026). CONCLUSION: The AC incidence and frequency of SD in children and adults with CAH are high. In contrast to the paediatric cohort, the majority of SD in adults was not in accordance with the DGE recommendations, underlining the need for structured and repeated education of patients with particular focus on transition.

Identifying the First Val281L Mutation Causing Nonclassic Congenital Adrenal Hyperplasia in the Central-East Region of Tunisia.

Nonclassic congenital adrenal hyperplasia (NCAH) is a genetic disorder characterized by mutations in the genes encoding enzymes involved in cortisol production, most commonly the 21-hydroxylase enzyme. Unlike classic congenital adrenal hyperplasia (CAH), NCAH typically presents later in life with milder symptoms. The diagnosis of NCAH can be challenging due to its nonspecific symptoms and variable presentation. Early detection is crucial for timely intervention and management, particularly in families with a history of the condition. We report a case of NCAH in a patient from the Central-East Region of Tunisia, in whom the subsequent genetic testing revealed a Val281Leu (V281L) mutation in the CYP21A2 gene. A 26-year-old female presented with facial hirsutism and irregular menstrual cycles. Physical examination revealed mild hirsutism and laboratory tests showed elevated levels of testosterone and 17-hydroxyprogesterone (17-OHP). A provisional diagnosis of NCAH was made, subsequently confirmed by an adrenocorticotropic hormone (ACTH) stimulation test demonstrating an exaggerated 17-OHP response. Genetic testing revealed heterozygosity for the V281L mutation. Family testing showed the patient's mother to be homozygous and the father heterozygous for the mutation. This report highlights the importance of recognizing subtle symptoms of NCAH for early diagnosis and management. Genetic testing aids in confirming the diagnosis and identifying carriers within families. Treatment with glucocorticoids aims to suppress adrenal androgen production and manage symptoms. Regular follow-up is essential to monitor treatment response and adjust medication as needed. NCAH can present with subtle symptoms, necessitating a high index of suspicion for a proper diagnosis. Genetic testing plays a crucial role in confirming the diagnosis and identifying carriers within families. Early intervention and regular follow-up improve outcomes in affected individuals. This report also underscores the significance of genetic testing in the management of NCAH and highlights the need for increased awareness about this condition among healthcare providers.

Prenatal diagnosis of congenital adrenal hyperplasia due to 21-hydroxylase deficiency through molecular genetic analysis of the CYP21A2 gene.

PURPOSE: Deficiency of 21-hydroxylase (21-OHD) is an autosomal recessively inherited disorder that is characterized by adrenal insufficiency and androgen excess. This study was performed to investigate the clinical utility of prenatal diagnosis of 21-OHD using molecular genetic testing in families at risk. METHODS: This study included 27 pregnant women who had previously borne a child with 21-OHD. Fetal tissues were obtained using chorionic villus sampling (CVS) or amniocentesis. After the genomic DNA was isolated, Sanger sequencing of CYP21A2 and multiplex ligation-dependent probe amplification were performed. The clinical and endocrinological findings were reviewed retrospectively. RESULTS: A total of 39 prenatal genetic tests was performed on 27 pregnant women and their fetal tissues. The mean gestational age at the time of testing was 11.7 weeks for CVS and 17.5 weeks for amniocentesis. Eleven fetuses (28.2%) were diagnosed with 21-OHD. Among them, 10 fetuses (90.9%) harbored the same mutation as siblings who were previously diagnosed with 21-OHD. Among these, 4 fetuses (3 males and 1 female) identified as affected were born alive. All 4 patients have been treated with hydrocortisone, 9α-fludrocortisone, and sodium chloride since a mean of 3.7 days of life. The male patients did not show hyponatremia and dehydration, although they harbored pathogenic variants associated with the salt-wasting type of 21-OHD. CONCLUSION: This study demonstrated the diagnostic efficacy and clinical consequences of diagnosis by prenatal genetic testing in families at risk for 21-OHD. All patients identified as affected were treated with hydrocortisone and 9α-fludrocortisone early after birth, which can prevent a life-threatening adrenal crisis.

Increased risk of nephrolithiasis: an emerging issue in children with congenital adrenal hyperplasia due to 21-hydroxylase deficiency.

PURPOSE: To investigate the incidence of nephrolithiasis in a cohort of children with congenital adrenal hyperplasia (CAH), and to study if there is an association with the metabolic control of the disease. METHODS: This study was designed as a multicenter 1 year-prospective study involving 52 subjects (35 males) with confirmed molecular diagnosis of CAH due to 21-hydroxylase deficiency (21-OHD). Each patient was evaluated at three different time-points: T0, T1 (+6 months of follow-up), T2 (+12 months of follow up). At each follow up visit, auxological data were collected, and adrenocorticotrophic hormone (ACTH), 17-hydroxyprogesterone (17-OHP), Δ4-androstenedione, dehydroepiandrosterone sulfate (DHEAS) serum levels, and urinary excretion of creatinine, calcium, oxalate and citrate were assayed. Moreover, a renal ultrasound was performed. RESULTS: The incidence of nephrolithiasis, assessed by ultrasound was 17.3% at T0, 13.5% at T1 and 11.5% at T2. At T0, one subject showed nephrocalcinosis. In the study population, a statistically significant difference was found for 17-OHP [T0: 11.1 (3.0-25.1) ng/mL; T1: 7.1 (1.8-19.9) ng/mL; T2: 5.9 (2.0-20.0) ng/mL, p < 0.005], and Δ4-androstenedione [T0: 0.9 (0.3-2.5) ng/mL; T1: 0.3 (0.3-1.1) ng/mL; T2: 0.5 (0.3-1.5) ng/mL, p < 0.005] which both decreased over the follow up time. No statistically significant difference among metabolic markers was found in the group of the subjects with nephrolithiasis, even if 17-OHP, DHEAS and Δ4-androstenedione levels showed a tendency towards a reduction from T0 to T2. Principal component analysis (PCA) was performed to study possible hidden patterns of associations/correlations between variables, and to assess the trend of them during the time. PCA revealed a decrease in the amount of the variables 17-OHP, Δ4-androstenedione, and ACTH that occurred during follow-up, which was also observed in subjects showing nephrolithiasis. CONCLUSIONS: our data demonstrated that children affected with 21-OHD can be at risk of developing nephrolithiasis. Additional studies are needed to clarify the pathogenesis and other possible risk factors for this condition, and to establish if regular screening of kidney ultrasound in these patients can be indicated.

[The androgenital syndrome: Don't just think about it in childhood!] / Das adrenogenitale Syndrom: Nicht nur im Kindesalter daran denken!

The androgenital syndrome: Don't just think about it in childhood!In adrenogenital syndrome, the body permanently produces too many male sex hormones. Rare, congenital metabolic diseases are usually discovered in infancy and can be treated at an early stage treated at an early stage, but sometimes they only become apparent in adolescence and adulthood.This article provides background knowledge for GPs.

Increased Prevalence of Accidents and Injuries in Congenital Adrenal Hyperplasia: A Population-based Cohort Study.

CONTEXT: It has been suggested that injuries and accidents are increased in females with congenital adrenal hyperplasia (CAH), but the prevalence is unclear. OBJECTIVE: To study the prevalence of injuries and accidents in females and males with CAH. DESIGN, SETTING, AND PARTICIPANTS: Patients with CAH (n = 714, all 21-hydroxylase deficiency) were compared with matched controls (n = 71 400). Data were derived by linking National Population-Based Registers. MAIN OUTCOME MEASURES: Prevalence of injuries and accidents. RESULTS: Mean age was 29.8 ± 18.4 years. Injuries were more prevalent in patients with CAH than in controls (relative risk, 1.34; 95% CI, 1.24-1.44), and this was found in both sexes (females: 1.43; 1.29-1.58; males: 1.25; 1.12-1.38). In the classical phenotype, the prevalence of injuries was higher, especially in females but not in the nonclassic phenotype. In the genotype groups, injuries were mainly increased in females. Head injuries were increased in all patients with CAH and in the different phenotypes and were mainly driven by females. More patients with CAH born before the introduction of neonatal screening had had an injury compared with controls (1.48; 1.35-1.62); this was seen in both sexes. In patients with CAH born after the introduction of screening, the prevalence of injuries was overall increased (1.20; 1.07-1.35), and in females with CAH but not in males. Accidents showed a similar pattern to injuries in all comparisons. CONCLUSION: Patients with CAH had an increased prevalence of both injuries and accidents, especially in females and in those born before the neonatal screening program. Patients with nonclassic phenotype were hardly affected.

Predictors of Cardiovascular Morbidities in Adults With 21-Hydroxylase Deficiency Congenital Adrenal Hyperplasia.

CONTEXT: The prevalence of cardiovascular and metabolic complications among adults with 21-hydroxylase deficiency (21OHD) is unknown. OBJECTIVE: We sought to determine the prevalence of cardiovascular and metabolic morbidities among adults with 21OHD and to identify clinical factors and biomarkers associated with cardiovascular outcomes. METHODS: A 10-year retrospective cross-sectional analysis was conducted on adult patients with confirmed 21OHD, aged 18 to 70 years, who had at least one clinical visit for assessment at the University of Michigan. The presence of cardiovascular diseases (CVDs) and other metabolic comorbidities was extracted from medical records based on International Classification of Diseases (ICD) codes. Medical treatments, glucocorticoid (GC) and mineralocorticoid doses, as well as specific biomarkers of disease control since age 18, were collected for analysis. RESULTS: A total of 254 patients with 21OHD, median age of 35 years (interquartile range, 28.25-46 y), were included in the analysis. The prevalence of CVDs in the entire cohort was 7.5%. An increase in prevalence was seen from early adulthood, reaching 25% in patients older than 60 years. Increasing age (adjusted odds ratio [OR], 1.05; 95% CI, 1.01-1.09), hypertension (OR, 4.27; 95% CI, 1.41-12.92), and higher GC doses (OR, 1.51; 95% CI, 1.11-2.06) were significantly associated with prevalent CVDs. Higher plasma renin activity was significantly associated with CVDs (OR, 1.07; 95% CI, 1.01-1.15) but not other biochemical markers of disease. CONCLUSION: Cardiometabolic morbidities are prevalent among adults with 21OHD. Hypertension, age, and GC exposure are the main predictive factors of established CVDs in our cohort.

Targeted long-read sequencing for comprehensive detection of CYP21A2 mutations in patients with 21-hydroxylase deficiency.

BACKGROUND: 21-Hydroxylase deficiency (21-OHD) is caused by pathogenic CYP21A2 variations. CYP21A2 is arranged in tandem with its highly homologous pseudogene CYP21A1P; therefore, it is prone to mismatch and rearrangement, producing different types of complex variations. There were few reports on using only one method to detect different CYP21A2 variants simultaneously. AIMS: Targeted long-read sequencing method was used to detect all types of CYP21A2 variants in a series of patients with 21-OHD. METHODS: A total of 59 patients with 21-OHD were enrolled from Peking Union Medical College Hospital. Long-range locus-specific PCR and long-read sequencing (LRS) were performed to detect the pathogenic variants in CYP21A2. RESULTS: Copy-number variants of CYP21A2 were found in 25.4% of patients, including 5.1% with 3 copies of CYP21A2, 16.9% with 1 copy of CYP21A2, and 3.4% with 0 copy of CYP21A2. The remaining 74.6% of patients had 2 copies of CYP21A2. Pathogenic variants were identified in all 121 alleles of 59 patients. Specifically, single-nucleotide variants and small insertions/deletions (< 50 bp) were detected in 79 alleles, of which conversed from CYP21A1P were detected in 63 alleles, and rare variants were found in the other 16 alleles. Large gene conversions (> 50 bp) from pseudogene were detected in 10 alleles, and different chimeric genes (CYP21A1P/CYP21A2 or TNXA/TNXB) formed by large deletions were detected in 32 alleles. Of all variants, p.I173N was the most common variant (19.0%). CONCLUSIONS: Our study demonstrated that targeted long-read sequencing is a comprehensive method for detecting CYP21A2 variations, which is helpful for genetic diagnosis in 21-OHD patients.

A MinION-based Long-Read Sequencing Application With One-Step PCR for the Genetic Diagnosis of 21-Hydroxylase Deficiency.

CONTEXT: Recently developed long-read sequencing (LRS) technology has been considered an option for CYP21A2 analysis. However, the clinical use of LRS for CYP21A2 analysis is limited. OBJECTIVE: This study's objective is to develop an efficient and low-cost LRS system for CYP21A2 screening. METHODS: A DNA fragment library was prepared in a single polymerase chain reaction (PCR) that covers the entire CYP21A2 gene and all known junctions caused by TNXB gene structural rearrangements, yielding a single 8-kb product of CYP21A2 or CYP21A1P/CYP21A2 chimera. After barcoding, the PCR products were sequenced on a MinION-based platform with Flongle Flow Cell R9.4.1 and R10.4.1. RESULTS: The reference genotypes of 55 patients with 21-hydroxylase deficiency (21OHD) were established using the conventional method with multiplex ligation-dependent probe amplification (MLPA) and nested PCR. LRS using Flongle Flow Cell R9.4.1 yielded consistent results. Additionally, the recently updated LRS "duplex" analysis with Flongle flow cell R10.4.1 was tested to reveal an advantage of accurately sequencing a variant located on the homopolymer region. By introducing a barcode system, the cost was reduced to be comparable to that of conventional analysis. A novel single-nucleotide variation was discovered at the acceptor site of intron 7, c.940-1G > C. We also identified a subtype of the classical chimeric junction CH2, "CH2a," in the region from the latter part of intron 5 to exon 6. CONCLUSION: We successfully established a novel low-cost and highly accurate LRS system for 21OHD genetic analysis. Our study provides insight into the feasibility of LRS for diagnosing 21OHD and other genetic diseases caused by structural rearrangements.

International Newborn Screening Practices for the Early Detection of Congenital Adrenal Hyperplasia.

INTRODUCTION: Newborn screening (NBS) programmes vary internationally in their approach to screening. Guidelines for congenital adrenal hyperplasia (CAH) screening recommend the use of two-tier testing and gestational age cutoffs to minimise false-positive results. The aims of this study were to describe (1) the approaches; (2) protocols used; and (3) available outcomes for CAH screening internationally. METHODS: All members of the International Society for Neonatal Screening were asked to describe their CAH NBS protocols, with an emphasis on the use of second-tier testing, 17-hydroxyprogesterone (17OHP) cutoffs, and gestational age and birth weight adjustments. If available, screening outcomes were requested. RESULTS: Representatives from 23 screening programmes provided data. Most (n = 14; 61%) recommend sampling at 48-72 h of life. Fourteen (61%) use single-tier testing and 9 have a two-tier testing protocol. Gestational age cutoffs are used in 10 programmes, birth weight cutoffs in 3, and a combination of both in 9. One programme does not use either method of adjusting 17OHP cutoffs. Case definition of a positive test and the response to a positive test differed between programmes. CONCLUSIONS: We have demonstrated significant variation across all aspects of NBS for CAH, including timing, the use of single versus two-tier testing and cutoff interpretation. Collaboration between international screening programmes and implementation of new techniques to improve screen efficacy will facilitate ongoing expansion and quality improvement in CAH NBS.

Genetics of 21-hydroxylase deficiency: Clinical presentation should guide the investigation.

A young couple applied for preconception counseling because of a case of congenital adrenal hyperplasia in the family. They were concerned about their risk of giving birth to a child with classic congenital adrenal hyperplasia. The case presented here demonstrates the complexity of the genetics of 21-hydroxylase deficiency and the way the clinical presentation should guide the genetic inquiry.